TY  - JOUR
AU  - Nikolić, Milan
AU  - Blagojević, Duško
AU  - Nikolić-Kokić, Aleksandra
AU  - Stanić, Dragana
AU  - Vranić, Danijela
AU  - Jones, David R.
AU  - Niketić, Vesna
AU  - Spasić, Mihajlo
PY  - 2007
PY  - 2007
UR  - https://radar.ibiss.bg.ac.rs/handle/123456789/552
AB  - In a previous study, it was shown that the lipid fraction, which is occasionally observed in red blood cell hemolysates, represents cholesterol (Ch) associated with phospholipid firmly bound to haemoglobin (termed Hb-Ch). The current study was conducted to investigate whether Hb-Ch could affect the primary anti-oxidant enzyme defence system in human erythrocytes. Sixty healthy volunteers were used for the current study. Group 1 consisted of 28 subjects without or with a low level of Hb-Ch. Group 2 comprised 32 subjects with a considerably higher level of Hb-Ch. The activities of erythrocyte superoxide dismutase, catalase, glutathione peroxidase and glutathione reductase, as well as the content of methaemoglobin (metHb) were measured in both groups. The results indicated that the amount of Hb-Ch neither influenced the activities of the erythrocyte anti-oxidant enzymes nor altered the level of metHb. However, a higher amount of Hb-Ch changed the correlations in the part of the anti-oxidant defence system relating to glutathione, suggesting increased peroxidative pressure from plasma lipids. Group 2 also had significantly increased concentrations of total plasma Ch and triglycerides. Together, these facts are strong indications that the anti-oxidant defence system in human erythrocytes finely retunes its composition according to plasma oxidative demands. .
AB  - U prethodnom radu pokazano je da lipidna frakcija koja se javlja u hemolizatu zdravih ljudi predstavlja holesterol (asosovan sa fosfolipidima) čvrsto vezan za hemoglobin (Hb-Ch). U ovom radu ispitivan je uticaj Hb-Ch na anti-oksidativni enzimski sistem u humanim eritrocitima. Određena je aktivnost superoksid-dizmutaze, katalaze, glutation-peroksidaze i glutation-reduktaze, kao i sadržaj met-hemoglobina (metHb) u eritrocitima 60 ljudi, podeljenih u dve grupe na osnovu količine Hb-Ch. Rezultati pokazuju da količina prisutnog Hb-Ch ne menja aktivnost merenih enzima, niti nivo metHb. Međutim, u grupi ispitanika sa povećanim sadržajem Hb-Ch zapažene su korelativne promene u delu anti-oksidativnog enzimskog sistema povezanog sa glutationom. U istoj grupi detektovane su i veće koncentracije ukupnog holesterola i triglicerida u plazmi, što zajedno ukazuje na povećani peroksidativni pritisak iz plazme. Ovi rezultati ukazuju da odbrambeni anti-oksidativni enzimski sistem u humanim eritrocitima prilagođava svoju organizaciju prema zahtevima iz svog okruženja. .
T2  - Journal of the Serbian Chemical Society
T1  - Da li holesterol vezan za hemoglobin utiče na anti-oksidativni enzimski sistem u humanim eritrocitima?
T1  - Does cholesterol bound to haemoglobin affect the anti-oxidant enzyme defence system in human erythrocytes?
IS  - 4
VL  - 72
SP  - 339
EP  - 345
UR  - https://hdl.handle.net/21.15107/rcub_ibiss_552
ER  - 

@article{
author = "Nikolić, Milan and Blagojević, Duško and Nikolić-Kokić, Aleksandra and Stanić, Dragana and Vranić, Danijela and Jones, David R. and Niketić, Vesna and Spasić, Mihajlo",
year = "2007, 2007",
abstract = "In a previous study, it was shown that the lipid fraction, which is occasionally observed in red blood cell hemolysates, represents cholesterol (Ch) associated with phospholipid firmly bound to haemoglobin (termed Hb-Ch). The current study was conducted to investigate whether Hb-Ch could affect the primary anti-oxidant enzyme defence system in human erythrocytes. Sixty healthy volunteers were used for the current study. Group 1 consisted of 28 subjects without or with a low level of Hb-Ch. Group 2 comprised 32 subjects with a considerably higher level of Hb-Ch. The activities of erythrocyte superoxide dismutase, catalase, glutathione peroxidase and glutathione reductase, as well as the content of methaemoglobin (metHb) were measured in both groups. The results indicated that the amount of Hb-Ch neither influenced the activities of the erythrocyte anti-oxidant enzymes nor altered the level of metHb. However, a higher amount of Hb-Ch changed the correlations in the part of the anti-oxidant defence system relating to glutathione, suggesting increased peroxidative pressure from plasma lipids. Group 2 also had significantly increased concentrations of total plasma Ch and triglycerides. Together, these facts are strong indications that the anti-oxidant defence system in human erythrocytes finely retunes its composition according to plasma oxidative demands. ., U prethodnom radu pokazano je da lipidna frakcija koja se javlja u hemolizatu zdravih ljudi predstavlja holesterol (asosovan sa fosfolipidima) čvrsto vezan za hemoglobin (Hb-Ch). U ovom radu ispitivan je uticaj Hb-Ch na anti-oksidativni enzimski sistem u humanim eritrocitima. Određena je aktivnost superoksid-dizmutaze, katalaze, glutation-peroksidaze i glutation-reduktaze, kao i sadržaj met-hemoglobina (metHb) u eritrocitima 60 ljudi, podeljenih u dve grupe na osnovu količine Hb-Ch. Rezultati pokazuju da količina prisutnog Hb-Ch ne menja aktivnost merenih enzima, niti nivo metHb. Međutim, u grupi ispitanika sa povećanim sadržajem Hb-Ch zapažene su korelativne promene u delu anti-oksidativnog enzimskog sistema povezanog sa glutationom. U istoj grupi detektovane su i veće koncentracije ukupnog holesterola i triglicerida u plazmi, što zajedno ukazuje na povećani peroksidativni pritisak iz plazme. Ovi rezultati ukazuju da odbrambeni anti-oksidativni enzimski sistem u humanim eritrocitima prilagođava svoju organizaciju prema zahtevima iz svog okruženja. .",
journal = "Journal of the Serbian Chemical Society",
title = "Da li holesterol vezan za hemoglobin utiče na anti-oksidativni enzimski sistem u humanim eritrocitima?, Does cholesterol bound to haemoglobin affect the anti-oxidant enzyme defence system in human erythrocytes?",
number = "4",
volume = "72",
pages = "339-345",
url = "https://hdl.handle.net/21.15107/rcub_ibiss_552"
}

Nikolić, M., Blagojević, D., Nikolić-Kokić, A., Stanić, D., Vranić, D., Jones, D. R., Niketić, V.,& Spasić, M.. (2007). Da li holesterol vezan za hemoglobin utiče na anti-oksidativni enzimski sistem u humanim eritrocitima?. in Journal of the Serbian Chemical Society, 72(4), 339-345.
https://hdl.handle.net/21.15107/rcub_ibiss_552

Nikolić M, Blagojević D, Nikolić-Kokić A, Stanić D, Vranić D, Jones DR, Niketić V, Spasić M. Da li holesterol vezan za hemoglobin utiče na anti-oksidativni enzimski sistem u humanim eritrocitima?. in Journal of the Serbian Chemical Society. 2007;72(4):339-345.
https://hdl.handle.net/21.15107/rcub_ibiss_552 .

Nikolić, Milan, Blagojević, Duško, Nikolić-Kokić, Aleksandra, Stanić, Dragana, Vranić, Danijela, Jones, David R., Niketić, Vesna, Spasić, Mihajlo, "Da li holesterol vezan za hemoglobin utiče na anti-oksidativni enzimski sistem u humanim eritrocitima?" in Journal of the Serbian Chemical Society, 72, no. 4 (2007):339-345,
https://hdl.handle.net/21.15107/rcub_ibiss_552 .

TY  - JOUR
AU  - Stojanović, Srđan D.
AU  - Spasić, Mihajlo
AU  - Stanić, Dragana
AU  - Nikolić, Milan
AU  - Raičević, Smiljana
AU  - Niketić, Vesna
PY  - 2005
PY  - 2005
UR  - https://radar.ibiss.bg.ac.rs/handle/123456789/550
AB  - The peroxynitrite-induced nitration of manganese superoxide dismutase (MnSOD) tyrosine residue, which causes enzyme inactivation, is well established. This led to suggestions that MnSOD nitration and inactivation in vivo, detected in various diseases associated with oxidative stress and overproduction of nitric monoxide (NO), conditions which favor peroxynitrite formation, is also caused by peroxynitrite. However, our previous in vitro study demonstrated that exposure of MnSOD to NO led to NO conversion into nitrosonium (NO+) and nitroxyl (NO–) species, which caused enzyme modifications and inactivation. Here it is reported that MnSOD is tyrosine nitrated upon exposure to NO, as well as that MnSOD nitration contributes to inactivation of the enzyme. Collectively, these observations provide a compelling argument supporting the generation of nitrating species in MnSOD exposed to NO and shed a new light on MnSOD tyrosine nitration and inactivation in vivo. This may represent a novel mechanism by which MnSOD protects cell from deleterious effects associated with overproduction of NO. However, extensive MnSOD modification and inactivation associated with prolonged exposure to NO will amplify the toxic effects caused by increased cell superoxide and NO levels.
AB  - Dobro je poznato da peroksinitrit izaziva nitrovanje ostataka tirozina u mangan-superoksid- dismutazi (MnSOD) što dovodi do inaktivacije enzima. Pokazano je da nitrovanje i inaktivacija MnSOD-a nastaje u raznim bolestima za koje je karakteristič an oksidativni stres i povećana produkcija azot-monoksida (NO). Pošto se pri ovim uslovima očekuje nastajanje peroksinitrita predloženo je da peroksinitrit izaziva nitrovanje i inaktivaciju MnSOD in vivo. U našem prethodnom radu pokazali smo da MnSOD katalizuje transformaciju NO u nitrozonijum (NO+) i nitroksil (NO–) reaktivne vrste, te identifikovali neke od modifikacija molekula enzima koje pri tome nastaju izazivajući njegovu inaktivaciju. U ovom radu je pokazano da pri izlaganju MnSOD azot-monoksidu dolazi i do nitrovanja ostatka tirozina u molekulu enzima, što doprinosi njegovoj inaktivaciji. Ovi rezultati ukazuju da pri interakciji MnSOD sa NO dolazi do nastajanja nitrujućih vrsta, što baca novo svetlo na proces nitrovanja ostataka tirozina i inaktivaciju MnSOD in vivo. Ovo može da predstavlja novi mehanizam kojim MnSOD štiti ćeliju odštetnih efekata izazvanih hiperprodukcijom azot-monoksida. Međutim ekstenzivne modifikacije i inaktivacija MnSOD do kojih dolazi pri produženom izlaganju enzima NO, uvećaće toksične efekte izazvane povećanim koncentracijama superoksida i NO u ćeliji.
T2  - Journal of the Serbian Chemical Society
T1  - Mangan-superoksid-dismutaza (MnSOD) katalizuje NO-zavisno nitrovanje ostatka tirozina
T1  - Manganese superoxide dismutase (MnSOD) catalyzes NO-dependent tyrosine residue nitration
IS  - 4
VL  - 70
SP  - 601
EP  - 608
UR  - https://hdl.handle.net/21.15107/rcub_ibiss_550
ER  - 

@article{
author = "Stojanović, Srđan D. and Spasić, Mihajlo and Stanić, Dragana and Nikolić, Milan and Raičević, Smiljana and Niketić, Vesna",
year = "2005, 2005",
abstract = "The peroxynitrite-induced nitration of manganese superoxide dismutase (MnSOD) tyrosine residue, which causes enzyme inactivation, is well established. This led to suggestions that MnSOD nitration and inactivation in vivo, detected in various diseases associated with oxidative stress and overproduction of nitric monoxide (NO), conditions which favor peroxynitrite formation, is also caused by peroxynitrite. However, our previous in vitro study demonstrated that exposure of MnSOD to NO led to NO conversion into nitrosonium (NO+) and nitroxyl (NO–) species, which caused enzyme modifications and inactivation. Here it is reported that MnSOD is tyrosine nitrated upon exposure to NO, as well as that MnSOD nitration contributes to inactivation of the enzyme. Collectively, these observations provide a compelling argument supporting the generation of nitrating species in MnSOD exposed to NO and shed a new light on MnSOD tyrosine nitration and inactivation in vivo. This may represent a novel mechanism by which MnSOD protects cell from deleterious effects associated with overproduction of NO. However, extensive MnSOD modification and inactivation associated with prolonged exposure to NO will amplify the toxic effects caused by increased cell superoxide and NO levels., Dobro je poznato da peroksinitrit izaziva nitrovanje ostataka tirozina u mangan-superoksid- dismutazi (MnSOD) što dovodi do inaktivacije enzima. Pokazano je da nitrovanje i inaktivacija MnSOD-a nastaje u raznim bolestima za koje je karakteristič an oksidativni stres i povećana produkcija azot-monoksida (NO). Pošto se pri ovim uslovima očekuje nastajanje peroksinitrita predloženo je da peroksinitrit izaziva nitrovanje i inaktivaciju MnSOD in vivo. U našem prethodnom radu pokazali smo da MnSOD katalizuje transformaciju NO u nitrozonijum (NO+) i nitroksil (NO–) reaktivne vrste, te identifikovali neke od modifikacija molekula enzima koje pri tome nastaju izazivajući njegovu inaktivaciju. U ovom radu je pokazano da pri izlaganju MnSOD azot-monoksidu dolazi i do nitrovanja ostatka tirozina u molekulu enzima, što doprinosi njegovoj inaktivaciji. Ovi rezultati ukazuju da pri interakciji MnSOD sa NO dolazi do nastajanja nitrujućih vrsta, što baca novo svetlo na proces nitrovanja ostataka tirozina i inaktivaciju MnSOD in vivo. Ovo može da predstavlja novi mehanizam kojim MnSOD štiti ćeliju odštetnih efekata izazvanih hiperprodukcijom azot-monoksida. Međutim ekstenzivne modifikacije i inaktivacija MnSOD do kojih dolazi pri produženom izlaganju enzima NO, uvećaće toksične efekte izazvane povećanim koncentracijama superoksida i NO u ćeliji.",
journal = "Journal of the Serbian Chemical Society",
title = "Mangan-superoksid-dismutaza (MnSOD) katalizuje NO-zavisno nitrovanje ostatka tirozina, Manganese superoxide dismutase (MnSOD) catalyzes NO-dependent tyrosine residue nitration",
number = "4",
volume = "70",
pages = "601-608",
url = "https://hdl.handle.net/21.15107/rcub_ibiss_550"
}

Stojanović, S. D., Spasić, M., Stanić, D., Nikolić, M., Raičević, S.,& Niketić, V.. (2005). Mangan-superoksid-dismutaza (MnSOD) katalizuje NO-zavisno nitrovanje ostatka tirozina. in Journal of the Serbian Chemical Society, 70(4), 601-608.
https://hdl.handle.net/21.15107/rcub_ibiss_550

Stojanović SD, Spasić M, Stanić D, Nikolić M, Raičević S, Niketić V. Mangan-superoksid-dismutaza (MnSOD) katalizuje NO-zavisno nitrovanje ostatka tirozina. in Journal of the Serbian Chemical Society. 2005;70(4):601-608.
https://hdl.handle.net/21.15107/rcub_ibiss_550 .

Stojanović, Srđan D., Spasić, Mihajlo, Stanić, Dragana, Nikolić, Milan, Raičević, Smiljana, Niketić, Vesna, "Mangan-superoksid-dismutaza (MnSOD) katalizuje NO-zavisno nitrovanje ostatka tirozina" in Journal of the Serbian Chemical Society, 70, no. 4 (2005):601-608,
https://hdl.handle.net/21.15107/rcub_ibiss_550 .